As per the Central Pollution Control Board's latest data, Bihar's Motihari is the most polluted city in India today, with an AQI of 413. It's followed by Purnia (378), Bettiah (377), Siwan (372), Araria (340), Katihar (337), Saharsa (322), Samastipur (317), Darbhanga (316), Buxar (313), Hisar (311), Fatehabad (306), Delhi (303) and Singrauli (302). Only Motihari is in 'severe' category.